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PubMed1984

Glucose-stimulated protein phosphorylation in the pancreatic islet.

A glucose-dependent phosphorylation of a 68kDa islet-cell protein was observed in islet-cell homogenates. In the presence of [gamma-32P]ATP the protein was phosphorylated only in the presence of alpha-D-glucose; other sugars were ineffective. Activation of the phosphorylation was half-maximal at 0.34 mM-glucose, 7 microM-ATP and 0.3 mM-Mg2+. Although the addition of glucose 6-phosphate in this design did not stimulate phosphorylation of the islet-cell protein, addition of glucose 6-phosphate to the radioactively labelled 68kDa protein rapidly removed (chased) the 32P label. The addition of presynthesized glucose 6-[32P]phosphate phosphorylated the 68kDa band in the islet-cell homogenate and also phosphorylated purified skeletal-muscle phosphoglucomutase. Phosphoglucomutase labelled thus by 32P was indistinguishable from the islet-cell phosphoprotein on electrophoretic gels. The 32P incorporated into both the islet-cell protein and the purified skeletal-muscle phosphoglucomutase was chased similarly by hexose phosphates. The purified phosphoglucomutase could also be phosphorylated by cyclic AMP-dependent protein kinase or by a mannoheptulose-insensitive process by the islet-cell cytosol. The phosphoenzyme formed thus was also dephosphorylated by D-glucose 6-phosphate and alpha-D-glucose 1-phosphate, suggesting that this may be a mechanism for generation of glucose 1,6-bisphosphate.

Animals↗

PubMed1996

3,7-Dichloroquinolinecarboxylic Acid Inhibits Cell-Wall Biosynthesis in Maize Roots.

The mode of action of the herbicide 3,7-dichloroquinolinecar-boxylic acid (quinclorac) was examined by measuring incorporation of [14C]glucose, [14C]acetate, [3H]thymidine, and [3H]uridine into maize (Zea mays) root cell walls, fatty acids, DNA, and RNA, respectively. Among the precursors examined, 10 [mu]M quinclorac inhibited [14C]glucose incorporation into the cell wall within 3 h. Fatty acid and DNA biosynthesis were subsequently inhibited, whereas RNA biosynthesis was unaffected. In contrast to the cellulose synthesis inhibitor 2,6-dichlorobenzonitrile, quinclorac strongly inhibited cellulose and a hemicellulose fraction presumed to be glucuronoarabinoxylan. However, the synthesis of (1->3),(1->4)-[beta]-D-glucans was only slightly inhibited. The degree of inhibition was time- and dose-dependent. By 4 h after treatment, the concentration that inhibited [14C]glucose incorporation into the cell wall, cellulose, and the sensitive hemicellulose fraction by 50% was about 15, 5, and 20 [mu]M, respectively. Concomitant with an inhibition of [14C]glucose incorporation into the cell wall, quinclorac treatment led to a marked accumulation of radioactivity in the cytosol. The increased radioactivity was found mostly in glucose and fructose. However, total levels of glucose, fructose, and uridine diphosphate-glucose were not changed greatly by quinclorac. These data suggest that quinclorac acts primarily as a cell-wall biosynthesis inhibitor in a susceptible grass by a mechanism that is different from that of 2,6-dichlorobenzonitrile.

Journal Article↗

PubMed1987

Hyperglycemia and hyperinsulinemia increase glucose utilization in fetal rat tissues.

In vivo measurement of glucose utilization by individual tissues of 19-day rat fetuses have been performed using radioactive 2-deoxy-D-glucose technique. In the basal state, glucose metabolic index was 13.6 +/- 0.5 ng.min-1.mg-1 for the whole fetus, 21 +/- 1 in the hindlimb muscles, 13 +/- 2 in the liver, and 16 +/- 2 in the brain, whereas the fetal heart had the highest value: 62 +/- 5 ng.min-1.mg-1. To raise the fetal glycemia, the basal maternal blood glucose concentration of 0.78 +/- 0.02 g/l was elevated to 1.04 +/- 0.02 g/l by mean of hyperglycemic clamps. The fetal hyperglycemia increased glucose metabolic index by 30-100% over basal values in all the tissues tested except in the brain. To raise fetal insulinemia, maternal euglycemic clamp with supraphysiological insulin concentrations were performed, then a fraction (1%) of exogenous insulin crossed the placenta. Fetal plasma insulin concentrations were thus elevated to 180 +/- 32 and 255 +/- 23 microU/ml. The fetal heart increased significantly its glucose metabolic index in response to the lower insulin level. Glucose metabolic index in hindlimb muscles and liver was increased by 50-100% for the highest insulin level, whereas the brain was unaffected by exogenous insulin. We conclude that glucose metabolic index is stimulated by physiological hyperglycemia in individual fetal tissues and that fetal tissues (heart, liver, and muscle) are sensitive to exogenous insulin.

Animals↗

PubMed1973

Glucose metabolism in the newborn rat. Temporal studies in vivo.

1. The concentrations of plasma d-glucose, l-lactate, free fatty acids and ketone bodies and of liver glycogen were measured in caesarian-delivered newborn rats at time-intervals up to 4h after delivery. Glucose and lactate concentrations decreased markedly during the first hours after delivery, but there was a delay of 60-90min before significant glycogen mobilization occurred. 2. The specific radioactivity of plasma d-glucose was measured as a function of time for up to 75min after the intraperitoneal injection of d-[6-(14)C]glucose and d-[6-(3)H]glucose into caesarian-delivered rats at 0, 1 and 2h after delivery. Calculations revealed that there was an appreciable rate of glucose formation at all ages studied, but immediately after delivery this was exceeded by the rate of glucose utilization. Around 2h post partum the rate of glucose utilization decreased dramatically and this coincided with a reversal of the immediately postnatal hypoglycaemia. 3. The specific radioactivity of plasma l-lactate and the incorporation of (14)C into plasma d-glucose and liver glycogen was measured as a function of time after the intraperitoneal injection of l-[U-(14)C]lactate into rats immediately after delivery. The logarithm of the specific radioactivity of plasma l-[U-(14)C]lactate decreased linearly with time for at least 60min after injection and the calculated rate of lactate utilization exceeded the rate of lactate formation. 4. (14)C incorporation into plasma d-glucose was maximal from 30-60min after injection of l-[U-(14)C]lactate and the amount incorporated at 60min was 23% of that present in plasma lactate. Although (14)C was also incorporated into liver glycogen the amount was always less than 3% of that present in plasma glucose. 5. The results are discussed in relationship to the adaptation of the newly born rat to the extra-uterine environment and the possible involvement of gluconeogenesis at this time before feeding is established.

Acetoacetates↗

PubMed1978

Insulin-like effect of bovine growth hormone in vivo as demonstrated by oxidation of 14C-U-glucose in diabetic rats.

The rate of appearance of radioactive carbon dioxide after injection of 14C-U-glucose, 14C-3,4-glucose, 14C-1-pyruvate, 14C-2-pyruvate, and 14C-1-acetate was measured in untreated, insulin-treated, and bovine growth hormone (bGH)-treated rats and compared to the results obtained from normal rats. The CO2 specific activity (SA) curve obtained from normal rats (mean of four experiments) injected with 14C-U-glucose reached a maximum value of 487 in 50 min and fell exponentially to near zero levels by 5 h. In contrast, the curve for untreated diabetic rats reached a peak of 247 in 17 min. In normal rats, 75% of the injected 14C was recovered as CO2 in 5 h compared to recovery of 31% by diabetic rats. Daily administration of 2 U protamine zinc insulin (PZI)/100 g body weight to diabetic rats returned these measurements to normal levels. A single injection of 400 microgram bGH (1.5 USP U/mg) into each diabetic rat 2 h before the start of the experiment yielded an SA curve and a percent recovery value comparable to results found with insulin treatment. The chronology of the insulin-like effect of the bGH was pertinent since other time intervals (including chronic bGH treatment) produced no similarity. Experiments carried out with 14C-3,4-glucose, 14C-1-pyruvate, 14C-2-pyruvate, and 14C-1-acetate suggest that bGH affects the glycolytic pathway at some point between the phosphorylation of glucose and the formation of pyruvate.

Acetates↗

PubMed1995

Sensitive northern blot hybridization using digoxigenin RNA probes for the mRNA detection of two glucose transporter isoforms.

Diseases involving glucose metabolism disorders are more and more prevalent. Therefore the question of glucose transporter gene expression is being addressed in experimental and clinical studies. Radioactive probes are generally used to assess glucose transporter mRNA levels, but these probes are short-lived, costly and harmful to the environment. Alternative methods that do not present these disadvantages, for example digoxigenin (DIG) labelled probes, might prove to be very interesting for the study of glucose transporter mRNA. The aim of the present work was to compare DIG-labelled cRNA probes to 32P-labelled cRNA probes in order to see whether or not the non-radioactive method can be used to assess glucose transporter gene expression. This work shows that DIG-labelled glucose transporter (GLUT1 and GLUT4) cRNAs are suitable probes for the assessment of these gene expressions. We have found that the DIG system offers a much higher sensitivity than the 32P system for both GLUT1 and GLUT4 mRNA detection. This represents a decisive advantage in human studies where tissue quantity is a limiting factor. In addition, stability, safety, time saving and cost reduction are other considerations that make DIG-labelled GLUT1 and GLUT4 cRNAs very attractive.

Animals↗

PubMed1978

Relative significance of exogenous and de novo synthesized fatty acids in the formation of rumen microbial lipids in vitro.

Mixed rumen microorganisms (MRM) or suspensions of rumen Holotrich protozoa obtained from a sheep were incubated anaerobically with [1-(14)C]linoleic acid, [U-(14)C]glucose, or [1-(14)C]acetate. With MRM, the total amount of fatty acids present did not change after incubation. An increase in fatty acids esterified into sterolesters (SE) and polar lipids at the expense of free fatty acids was observed. This effect was intensified by the addition of fermentable carbohydrate to the incubations. Radioactivity from [1-(14)C]linoleic acid was incorporated into SE and polar lipids with both MRM and Holotrich protozoa. With MRM the order of incorporation of radioactivity was as follows: SE > phosphatidylethanolamine > phosphatidylcholine. With Holotrich protozoa, the order of incorporation was phosphatidylcholine > phosphatidylethanolamine > SE. With MRM the radioactivity remaining in the free fatty acids and that incorporated into SE was mainly associated with saturated fatty acids, but a considerable part of the radioactivity in the polar lipids was associated with dienoic fatty acids. This effect of hydrogenation prior to incorporation was also noted with Holotrich protozoa but to a much lesser extent. Small amounts of radioactivity from [U-(14)C]glucose and [1-(14)C]acetate were incorporated into rumen microbial lipids. With protozoa incubated with [U-(14)C]glucose, the major part of incorporated radioactivity was present in the glycerol moiety of the lipids. From the amounts of lipid classes present, their radioactivity, and fatty acid composition, estimates were made of the amounts of higher fatty acids directly incorporated into microbial lipids and the amounts synthesized de novo from glucose or acetate. It is concluded that the amounts directly incorporated may be greater than the amounts synthesized de novo.

Acetates↗

PubMed1969

Catabolite inhibition: a general phenomenon in the control of carbohydrate utilization.

When Escherichia coli is grown in synthetic medium with radioactive galactose or lactose as the carbon source, the addition of glucose rapidly inhibited utilization of the radioactive substrate, whether the formation of (14)CO(2) or acid-insoluble products was measured. The inhibition was reversed after the removal of glucose. Experiments with mutants blocked in subsequent steps of galactose and lactose metabolism demonstrated that the inhibition occurs prior to the formation of the first metabolic product. The utilization of a variety of sugars, including maltose, lactose, mannose, galactose, l-arabinose, xylose, and glycerol was inhibited by glucose. Of a number of carbohydrates tested as potential inhibitors, only glucose and, to a lesser extent, glucose-6-phosphate (G-6-P) were capable of inhibiting the utilization of all of the substrates. Glucose did not inhibit G-6-P utilization but G-6-P inhibited glucose utilization. With all substrates, except glycerol, there was a delay before the onset of inhibition by G-6-P. We conclude that E. coli has a general regulatory mechanism, termed catabolite inhibition, which controls the activity of early reactions in carbohydrate metabolism, allowing certain substrates to be utilized preferentially.

Antimetabolites↗

PubMed2001

The effect of exogenous sugars on the control of flux by adenosine 5'-diphosphoglucose pyrophosphorylase in potato tuber discs.

The aim of this work was to investigate the effect of exogenous sugars on the extent to which starch synthesis in potato ( Solanum tuberosum L.) is controlled by adenosine 5'-diphosphoglucose pyrophosphorylase (EC 2.7.7.27; AGPase). Tuber discs were incubated in the presence of a range of concentrations of glucose and sucrose, and metabolic fluxes measured following the supply of [U-14C]glucose and measurement of the specific radioactivity of the hexose phosphate pool. In the presence of glucose there was a marked increase in the flux through glucose-phosphorylating hexokinase, and at high concentrations of external glucose this led to a stimulation of the rate of starch and sucrose synthesis relative to those measured in the presence of sucrose. In the presence of glucose the ratio of the rate of starch synthesis to the rate of glycolysis was higher than in the presence of sucrose. Similar effects of glucose were observed at two stages of tuber development. We conclude that the presence of glucose perturbs the carbohydrate metabolism of tuber discs so that starch synthesis is favoured. In order to determine the extent to which AGPase controls flux, we measured fluxes in wild-type plants and transgenic plants with reduced AGPase activity as a result of the expression of a cDNA encoding the B subunit in the antisense orientation. In the presence of sucrose a reduction in AGPase activity had a greater impact on the rate of starch synthesis than in the presence of glucose. The flux control coefficient of AGPase over starch synthesis was higher in the presence of sucrose (0.7-0.9) than in the presence of glucose (0.4-0.6). Conversely, the impact of reduced AGPase activity on the rate of sucrose synthesis was lower in the presence of sucrose than glucose. In the presence of 200 mM sucrose the flux control coefficient of AGPase over the rate of sucrose synthesis was not significantly different from zero. This demonstrates that the nature of the sugar supplied to potato tuber discs can have a major influence on the distribution of control within metabolism. These data were also used to investigate the relationship between demand for ATP and the rate of hexose phosphate entry into glycolysis. A very strong correlation between ATP demand and glycolytic flux was demonstrated.

Carbohydrate Metabolism↗

PubMed1988

Glucose metabolism by Lactobacillus divergens.

Earlier studies on the fermentation of D-[1-14C]- and D-[3,4-14C]glucose by Lactobacillus divergens showed that lactate was the major fermentation product and that it was probably produced by glycolysis. It was therefore recommend that L. divergens be reclassified as a homofermentative organism. In the present investigation, products of D-[1-14C]-,D-[2-14C]- and D-[3,4-14C]glucose fermented by L. divergens were isolated, and their specific radioactivities and the distribution patterns of radioactivity in their C-atoms were determined. The positional labelling patterns of the fermentation products, their specific radioactivities and their concentrations confirmed that glucose is degraded via the glycolytic pathway. Some secondary decarboxylation/dissimilation of pyruvate to acetate, formate and CO2 was also observed. These results provide conclusive proof that L. divergens is indeed a homofermentative organism. Results obtained with D-[U-14C]glucose showed that approximately three-quarters of the lactate but less than 10% each of the formate and acetate were produced from glucose. The remainder was presumably derived to a varying degree from endogenous non-glucose sources such as fructose and/or amino acids.

Acetates↗

PubMed1988

Characterization of d-Enzyme (4-alpha-Glucanotransferase) in Arabidopsis Leaf.

Two major forms of d-enzyme (4-alpha-glucanotransferase, EC 2.4.1.25) were successfully separated from most of the amylase activity using FPLC-Mono Q column chromatography. Transfer of a maltosyl group was observed upon the incubation of d-enzyme with maltotriose and d-[U-(14) C]glucose. About 4.5% of the radioactivity was transferred to maltotriose in 2 hours. End product analysis showed the accumulation of glucose and maltopentaose from maltotriose within the first 10 minutes of the reaction. Several other maltodextrins were also observed with longer incubation times, although maltose was never produced. A quantitative measurement of maltodextrin production from the reaction of [(14) C]maltotriose with d-enzyme showed that the quantity of maltotriose decreased from 100% to 31% after 3 hours incubation, while glucose, maltotetraose, maltopentaose, maltohexaose, maltoheptaose, maltooctaose, and higher maltodextrins increased in amount. Glucose is the major product throughout the course of the reaction of d-enzyme with maltotriose. Maltotriose, in addition to glucose, are the major products in the reaction of d-enzyme with maltodextrins with a chain length greater than maltotriose. This study confirms the existence of a transglycosylase that disproportionates maltotriose and higher maltodextrins by transferring maltosyl or maltodextrinyl groups between maltodextrins resulting in the production of glucose and different maltodextrins, but not maltose, in leaf tissue with enzymic properties very similar to the previously reported d-enzyme in potato.

Journal Article↗

PubMed1981

Effects of intravenous versus intragastric glucose pretreatment on triglyceride secretion by perfused livers of fed rats.

The effects of the route of administration of 450 mg [U-14C]glucose to 250-g fed rats in vivo on the subsequent release of triglycerides from the perfused liver was studied. Livers were perfused for 180 min using a nonrecycling medium containing 10 mM glucose, 2 mM lactate, 0.2 mM pyruvate, and 100 microunits/mL porcine insulin. Biopsies were obtained at the beginning and end of the perfusions. The perfusate was collected and the secreted triglycerides were analyzed. Slower absorption of the intragastric glucose load contrasted with the rapid entry of the intravenous load; however, the total liver counts were not significantly affected by the route of glucose delivery. Hepatic glycogen concentration was also not significantly different, but the percent of total liver counts which was present in glycogen was significantly higher after intravenous glucose. The majority of the radioactivity in the livers of both groups of rats was present in water-soluble metabolites, with lesser amounts in triglycerides and phospholipids. Radioactivity in hepatic triglycerides declined significantly during perfusion only in the rats which had received glucose intravenously. The mean rate of triglyceride secretion from the livers of rats receiving the glucose intravenously was significantly lower than that of the rats receiving glucose intragastrically (0.21 +/- 0.05 vs. 0.97 +/- 0.28 mg/g liver per 180 min, p less than 0.05). The route of glucose administration affects both entry of glucose into the blood and subsequent hepatic triglyceride metabolism and secretion.

Absorption↗

PubMed1974

Biosynthesis of glycosyldiglycerides in Mycobacterium smegmatis.

A particulate enzyme preparation from Mycobacterium smegmatis catalyzes the transfer of [(14)C]galactose from uridine 5'-diphosphate (UDP)-[(14)C]galactose and of [(14)C]glucose from UDP-[(14)C]glucose into chloroform-soluble products. The radioactive neutral lipids were purified by passage through diethylaminoethyl-cellulose, followed by thin-layer chromatography. When UDP-glucose was used as substrate, two major radioactive lipids were obtained; one had a hexose-glucose-glycerol ratio of 1:1:1. The second product had a hexose-glycerol ratio of 2:1 and, in addition to glucose, contained lesser amounts of mannose and galactose. With UDP-galactose as substrate, two radioactive products were observed that were chromatographically indistinguishable from the [(14)C]glucosyl-labeled mono- and diglycosyldiglyceride. Palmitate and oleate were the predominant fatty acid constituents in these lipids and were present in equimolar amounts in all of the products examined. The products have thus been identified as monoglycosyldiglyceride and a diglycosyldiglyceride containing glucose as the major hexose along with mannose and galactose. Properties of the galactosyl and glucosyl transferases are described.

Carbon Radioisotopes↗

PubMed1988

Topography of basal glucose utilization in the hippocampus determined with [1-14C]glucose and [6-14C]glucose.

The activity of the pentose phosphate shunt was assessed under basal conditions in subregions of the hippocampus by measuring the uptake and retention of [1-14C]glucose and [6-14C]glucose and their 14C-labelled metabolites. The relative and absolute retention of carbon-14 from each of the two compounds was nearly identical in all regions examined. For each compound, the highest accumulation of 14C occurred in the granule cell layer of the dentate gyrus and in the pyramidal cell layer. Relatively high retention of radioactivity was also found in the molecular layer of dentate gyrus and in the stratum lacunosum-molecular. The stratum radiatum and stratum oriens contained the lowest levels of radioactivity among hippocampal regions. The equal retention of radioactivity from [1-14C]glucose and [6-14C]glucose implies that pentose phosphate shunt activity is very low throughout the hippocampus under the conditions of this study. The uptake and retention of radioactivity was evaluated in different hippocampal regions 10 or 30 min following intravenous injection of [1-14C]glucose. Although there was significantly more radioactivity at 30 min than at 10 min, the same topographic pattern of radioactivity within the hippocampus was observed in rats after both survival periods, indicating that an equal fraction of the [1-14C]glucose utilized in different hippocampal regions is oxidized to 14CO2 under these conditions. Most regions of high glucose utilization in the hippocampus determined with [1-14C]glucose and [6-14C]glucose correspond to regions of intense histochemical staining for cytochrome oxidase reported in the literature.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1978

The synthesis of complex-type oligosaccharides. I. Structure of the lipid-linked oligosaccharide precursor of the complex-type oligosaccharides of the vesicular stomatitis virus G protein.

The synthesis of the complex-type oligosaccharide unit of the vesicular stomatitis virus G protein is initiated by the en bloc transfer of a high molecular weight oligosaccharide from a lipid carrier to the nascent polypeptide. Following transfer the oligosaccharide is "processed" by removal of glucose and mannose residues and the sugars that constitute the outer branches of the complex-type oligosaccharide are added. The structure of the oligosaccharide moiety of the lipid-linked precursor has been elucidated in order to further define the steps involved in processing. Since it was not feasible to obtain adequate amounts of material for standard structural studies, most of the structural studies were performed on radiolabeled material, with radioactivity incorporated differentially into glucose, mannose, and N-acetylglucosamine. Based on endo-beta-N-acetylglucosaminidase CII digestion, alpha-mannosidase digestion, acetolysis, Smith periodate degradation, methylation analysis, and periodate oxidation, we propose the following structure for the oligosaccharide moiety of the lipid-linked oligosaccharide.

Carbohydrates↗

PubMed1983

High-energy diets produce different effects on fatty acid synthesis in brown adipose tissue, white adipose tissue and liver in the rat.

The influence of feeding rats a high-energy diet for 7 days on fatty acid synthesis in brown adipose tissue, white adipose tissue and liver of the rat was investigated. The incorporation of 3H2O and [U-14C]glucose into fatty acid was measured in vivo. The rats fed the high-energy diets had higher rates of fatty acid synthesis in white adipose tissue than the controls fed on chow, while fatty acid synthesis in brown adipose tissue and liver was either decreased or unchanged relative to that of controls fed on chow. After an oral load of [U-14C]glucose the incorporation of radioactivity into tissue fatty acid was several-fold higher in brown adipose tissue than in white adipose tissue in rats fed on chow. In rats fed the high-energy diets, incorporation of radioactivity into fatty acid in brown adipose tissue was decreased while that into white adipose tissue was either increased (Wistar rats) or unchanged (Lister rats).

Adipose Tissue↗

PubMed1985

Age-related changes of glucose metabolism in rat cerebral cortex with reference to glucose-derived amino acids.

The parietal cortical slices obtained from 8 week-old (young) and 78 week-old (middle-aged) male Wistar rats were incubated with D-[U-14C]glucose in oxygen-saturated Gey's balanced salt solution. Subsequently, the radioactivities of liberated CO2 and glucose-derived amino acids (alanine, aspartate, GABA, glutamate and glutamine) obtained from the slices were measured. In the middle-aged rats as compared to the young rats, the amount of radioactivity of CO2 (P less than 0.01) and glutamate (P less than 0.05) showed a significant reduction with glutamine unchanged, while that of alanine (P less than 0.01), aspartate (P less than 0.05) and GABA (P less than 0.05) increased significantly. The results indicate that with advancing age the overall glucose oxidation in the cerebral cortex declines but the metabolic pathway to form amino acids is not uniformly suppressed. Therefore, the above characteristic glucose metabolism could be related to the development of heterogeneous enzyme activities associated with aging in the brain.

Aging↗

PubMed1976

Spirochaeta halophila sp. n., a facultative anaerobe from a high-salinity pond.

A facultatively anaerobic spirochete isolated from a high-salinity pond grew optimally when 0.75 M NaCl, 0.2 M MgSO4, and 0.01 M CaCl2 were present in media containing yeast extract, peptone, and a carbohydrate. The organism failed to grow when any one of these three salts was omitted from the medium. Aerobically-grown colonies of the spirochete were red, whereas anaerobically-grown colonies showed no pigmentation. Non-pigmented mutants of the spirochete were isolated. The spirochete used carbohydrates, but not amino acids, as energy sources. Glucose was fermented to CO2, H2, ethanol, acetate, and a small amount of lactate. Determinations of radioactivity in products formed from glucose-1-14C and enzymatic assays indicated that glucose was dissimilated to pyruvate mainly via the Embden-Meyerhof pathway. Pyruvate was metabolized through a clostridial-type clastic reaction. Cells growing aerobically performed an incomplete oxidation of glucose mainly to CO2 and acetate. Comparison of aerobic and anaerobic growth yields indicated that oxidative phosphorylation occurred in cells growing aerobically. The guanine + cytosine content of the DNA of the spirochete was 62 moles %. It is proposed that the spirochete described herein be considered a new species and that it be named Spirochaeta halophila.

Aerobiosis↗